Landfill Methane and Climate Change by bKA8Sb3

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									    California Integrated Waste Management Board


      Landfill Methane and Climate Change

       • Overview of Science and Regulation
       • Status of Climate Action Team and
         AB 32 Landfill Methane Capture Strategy



                                                    Scott Walker, PE, CEG
                   California Integrated Waste Management Board (CIWMB)
                                        LEA/CIWMB Partnership Conference
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                                                          October 16, 2007
    California Integrated Waste Management Board

                           Landfill Gas
    •   Landfill gas is a complex decomposition product of
        waste in a sanitary landfill. Composition:
        – Methane (45-60%) and carbon dioxide (40-60%).
        – N2 (2-5%), O2 (0.1-1%), NH3 (0.1-1%), Sulfides (0-1%),
            H2 (0-0.2%), CO (0-0.2%).
        –   Non-Methane Organic Compounds (NMOCs) 0.01-
            0.6%, other non-NMOC HAPs/TACs (e.g., Hg).
    •   Potential threats to public health and environment:
        – Explosive (5-15% methane in air).
        – Asphyxiant in confined spaces.
        – Odorous, toxic, and ozone precursor trace gases.
        – Methane contributes to climate change emissions.
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    California Integrated Waste Management Board

                Regulation of Landfill Gas
    •   Air Quality: Local Air Districts and ARB
        –   NMOCs, VOCs, TACs/HAPS, odors, and criteria
            pollutants (NOx, CO, PM) from control devices.
        –   District Rules and Permits which reflect Federal Clean
            Air Act NSPS/EG Rules and Title V Permits.
        –   Climate Change/Greenhouse Gases: ARB (AB 32 2006).
    •   Water Quality: SWRCB/RWQCBs
        –   Title 27 California Code of Regulations (27 CCR); Waste
            Discharge Requirements (WDRs).
    •   Explosive Gas Migration: CIWMB/LEA
        –   27 CCR §§20918-20939 which reflect RCRA Subtitle D;
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            Solid Waste Facility Permit (SWFP).
    California Integrated Waste Management Board
                  Landfill Gas Migration




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    California Integrated Waste Management Board

         Landfill Methane as Greenhouse Gas
     •   Why is methane a greenhouse gas (GHG)?
          – Methane absorbs terrestrial infrared radiation
              (heat) that would otherwise escape to space.
          –   Methane is 23x more potent by weight than CO2 .
          –   Higher rate of increase than CO2 and reduction
              will have more rapid climate change response.
     •   USEPA estimates natural sources 40% and
         anthropogenic sources 60% (landfills, fossil fuel
         production, animal husbandry (livestock and
         manure), rice cultivation, biomass burning).

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    California Integrated Waste Management Board

                  Landfill Methane (cont.)
    •   Landfill methane is produced by anaerobic biologic
        processes (methanogen bacteria) and depends on
        waste quantity, type, moisture, climate, and age.
    •   Methane not captured (naturally oxidized, in
        subsurface, or removed by controls) is released to
        atmosphere as fugitive emissions.
    •   Methane emissions typically estimated (with high
        uncertainty) by models and by direct measurement.
    •   Public domain models include EPA LandGEM
        (www.epa.gov/ttn/catc/products.html#software) and IPCC.
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         TYPICAL LANDFILL GAS GENERATION PATTERN
    California Integrated Waste Management Board




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    California Integrated Waste Management Board

          Landfill Methane Capture Efficiency

    •   Capture efficiency is controversial and a key
        measure of performance in reducing emissions.
    •   Estimated based on modeled gas generation and
        measured gas that is flared or recovered.
    •   Default capture efficiencies based on USEPA are
        75% (with control) and 10% for natural oxidation.
        Actual capture may be higher or lower.
    •   Active projects to reduce uncertainty (CEC Study).


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    California Integrated Waste Management Board
                                     Landfill Gas Models- USEPA LandGEM
                                               (Example 250,000 Tons/Year; Closure Year 30)
                                   1,800
                                   1,600
                                                                              Dry Site (k=0.02)
                                   1,400
       Methane Generation (scfm)




                                                                              Conventional Site (k=0.04)
                                   1,200

                                   1,000                                      Bioreactor (k=0.7)

                                    800

                                    600
                                    400

                                    200
                                      0
                                           0     10    20   30    40    50    60     70      80    90      100
9                                                                 Year From Start
       California Integrated Waste Management Board
                              Landfill Gas Models Versus “Real World”
                                     Bradley LF 19-AR-0004
                            7000
                                                   Closure 2006
                            6000
     LFG Flow 50% Methane




                            5000

                            4000                                    LandGEM
                                                                    (Model)
                            3000
                                                                    Actual
                            2000

                            1000

                              0
                              60

                              65

                              70

                              75

                              80

                              85

                              90

                              95

                              00

                              05

                              10

                              15

                              20

                              25

                              30

                              35
                            19

                            19

                            19

                            19

                            19

                            19

                            19

                            19

                            20

                            20

                            20

                            20

                            20

                            20

                            20

                            20
                                           Year
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     California Integrated Waste Management Board

           Landfill Methane Direct Measurement
                       Lancaster Landfill 9/12/07
                                                              Opposite RPM
                                                              Detectors

                                                                 Wellhead
                                                                 Penetration

                                                                Radial Flux
                                                                Chambers




        Flux Chamber
                          Radial Plume
                          Mapping (RPM)                 Climate Station
                          Mirror                        Scissor Lift




                                            RPM
                                            Detectors
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     California Integrated Waste Management Board

               CEC Study (Bogner/Spokas)
     • Investigate the use of data collected by CIWMB and
       Local Air District as predictive parameters.
     • Collect 2 years of field data, using flux chambers to
       obtain emission factors. RPM at one landfill to
       provide additional field validation.
     • Goal to create scientifically sound and practical
       detailed landfill methane emissions model and
       inventory methodology to account for variation
       across landfill site-specific characteristics, climate,
       and oxidation in cover soils.
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     California Integrated Waste Management Board

                  Landfill Methane Role
              in Greenhouse Gas Inventory
      • AB 32 ARB draft GHG inventory released 8/22/07
        (final by 1/1/08) www.arb.ca.gov/cc/ccei/emsinv/emsinv.htm
      • Net 1990 GHG level is 436 MMTCO2E required by
        2020 (2004- 497). Energy/Fuel Combustion (1A)-
        392 in 1990 or 90% of total net emissions.
      •   Landfill methane (4A)- 6.58 MMTCO2E in 1990 or
          1.5% of total net emissions; in 2004 emissions
          reduced to 5.83 or 1.2% total.
      •   Livestock methane (3A)- 11.67/1990; 13.92/2004

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     California Integrated Waste Management Board

               Climate Action Team (CAT)
            Landfill Methane Capture Strategy

      •   Install new systems and increase methane
          capture efficiencies (included in AB 32 ARB
          Discrete Early Action Measure; estimated 2-4
          MMTCO2E reductions)
      •   Increase recovery of landfill methane (>1.2
          MMTCO2E in avoided emissions from offset
          fossil fuel combustion).



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     California Integrated Waste Management Board

           Landfill Methane Control Systems

       1200
                                            Statewide Landfill
       1000                                 Waste In Place
                                            (million tons)
        800
                                            Waste In Place-
        600                                 With Methane Gas
                                            Control Systems
        400
                                            Waste In Place- No
                                            Methane Control
        200
                                            System
          0
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                 1990         2006
     California Integrated Waste Management Board

          AB 32 Discrete Early Action Measure

     • One of three measures adopted by ARB will reduce
       landfill methane emissions by requiring control
       systems where systems not currently required and
       performance standards for maximum capture.
     • Regulatory concepts released for public workshop
       on 10/10/07. www.arb.ca.gov/cc/ccea/landfills/landfills.htm
     • Based on ARB actions, CIWMB to consider
       regulatory concepts within its purview if necessary
       to support ARB actions.


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     California Integrated Waste Management Board

         Landfill Methane Capture BMP Study

      • CIWMB-funded ($150K) study by SCS Engineers
        to develop practical Best Management Practices
        (BMPs) to maximize landfill methane capture:
         – Early Installation of LFG System
         – Maximizing LFG System Design
         – Landfill Design/Operational Practices
         – Enhanced Monitoring and Metrics
      • To be completed early 2008; will tie in with ARB
        Early Action Measure and CIWMB rulemaking.
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     California Integrated Waste Management Board

         Landfill Methane and Climate Change

       • For additional information contact:
         Stephanie Young              Scott Walker
         SYoung@ciwmb.ca.gov          swalker@ciwmb.ca.gov
         916-341-6357                 916-341-6319




                                   LEA/CIWMB Partnership Conference
18                                                 October 16, 2007

								
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